Smell Prediction

Barani Raman of the School of Engineering and Applied Science at Washington University in St. Louis and his team has conducted a research to understand the process through which various odours trigger neurons in the brain and help us react. Raman made use of locusts in the research as they possess a simple sensory system which is ideal for brain activity.

He used a computer controlled pneumatic pump to administer a puff of an odour to the locust. The locust smells with the help of olfactory receptor neurons (neurons that detect odour molecules) in its antennae, which are similar to sensory neurons in our nose. A few seconds after the puff was given, the locust was rewarded with a piece of grass, as a form of pavlovian conditioning (reaction to a sound or smell). The locust reacted to the smell henceforth by opening up its finger-like projections close to the mouthparts, predicting they’d be rewarded. The locusts also recognized the correct odour even when other odours were administered to distract them.

The research team was happy with the speed with which the insects responded. The locusts’ brain had processes chemical cues in a rapid fashion. Raman had spent a decade learning about the olfactory system and his main aim is to find the computations to trigger the precursory cue that informs the brain about a warning or an alert. The research has helped to learn the neural activity of the brain and could help in the future with non-invasive chemical sensing in homeland security applications to detect volatile chemicals or in diagnostics.